M.  Baidaa, Rehab  K. Al-Shemary, 
    Chelation of N,O-Donor Attached Schiff Base Ligand Bear Cephalexin Towards Co(II), Ni(II),
Cu(II) and Cd(II): Syntheses, Structures, Antimicrobial Activities and Cytotoxic Studies,
    International Journal of Tropical Medicine,
    Volume 16,Issue 2,
    2021,
    Pages 15-23,
    ISSN 1816-3319,
    ijtmed.2021.15.23,
    (https://makhillpublications.co/view-article.php?doi=ijtmed.2021.15.23)
    Abstract: This study comprised the preparation of Schiff
base derivatives of cephalexin antibiotic by condensation
reaction with Isatin. Metal complexes of the Schiff base
ligands with Co(II), Ni(II), Cu(II), Cd(II) ions were
prepared by reacting the ligand with the metal salts in
refluxing ethanol. The chemical structure of the ligand, as
well as the stereo-chemical structure and arrangements of
the synthesized metal complexes were mentioned relying
upon the outcomes given from TG analysis and CHN,
mass, NMR, atomic absorption and FTIR,
spectrophotometry, electronic spectra, measurements of
conductivity and magnetic moments. The mole ratio of
(ligand: metal ion) was (2:1) with bi-dentate linking
demeanors of the chelating ligand with the metal ions.
The IR spectra clarified a bidentate ligand which chalets
through nitrogen atom of imino from azomethine bond
and the oxygen atom of the carbonyl. UV-Vis
spectrophotometry showed the characteristic absorption
bands conformable to an octahedral arrangement for all
metal complexes. The overall form found from empirical
values was found to be M(OADC)<sub>2</sub>(H2O)<sub>2</sub> where M =
Co(II), Ni(II), Cu(II), Cd(II) and (OADC) = Schiff base
ligand. This composition was further confirmed by
thermal analysis and their thermal constancy in nitrogen
atmosphere was carried out. The study of antibacterial
appeared that the efficiency of metal complexes is higher
than the one established for the free Schiff base ligand.
Lastly, the cytotoxicity of [OADC] ligand and its
complexes were screened on the cell line of Hep G2.
[OADC] ligand appears good efficacy with the cell line of
Hep G2 than complexes.
    Keywords: Chelation;cephalexin;Schiff base;antimicrobial;cytotoxic studies